GLOBAL WARMING: ARE WE TO BLAME?
Previous articles and letters from the editor have made clear that Discover supports the idea that global warming is caused by humans, about which I have no qualms. However, I often find conflicting messages within your pages. In September's Discover Dialogue, meteorologist William Gray says that nearly all his colleagues who have been around 40 or 50 years are "skeptical as hell" about global warming. He goes on to say that human-induced global warming is a conclusion arrived at by those who "don't know anything about how the atmosphere functions," that scientific support for the idea arises from a vested interest in funding, and that his own research may have been hurt for speaking out about this situation. Despite this, in the same issue the article "Up a Creek" begins with the statement that "few scientists of any political persuasion question the reality of human-induced global warming." All this leaves the concerned reader somewhat confused. I want to make informed decisions on this issue, but it seems that behind the headlines lies an undercurrent of valid scientific skepticism. Your readers would be well served by a comprehensive presentation covering the evidence and the scientists on both sides.
San Diego, California
Mr. Rollo is not the first to notice the discrepancy, nor did we publish the issue without being aware of it (we discussed putting references in each article to the other). Discover doesn't interpret science; it reports it. There are many points of view out there about global warming. It's an accurate statement that most scientists now accept that human-induced global warming is real. It's equally accurate that a few scientists, including some meteorologists who've been in the field for years, have doubts. We hoped readers would be pleased that we were willing to look at and report both sides of the issue. In the future we will address the following questions squarely: What do scientists really know about global warming, and what do they not know? —Stephen Petranek, editor in chief
I read "Up a Creek" with an increasing sense of dismay. It sounded like a group of ideologues arguing philosophy. Such discourses may be impressive in the halls of academe, but I can discern little constructive purpose to them. These people could put their minds to much better use by realistically assessing the potential contributions, feasibilities, risks, and economic viabilities of the various approaches to energy supply with due attention to the estimated time frames and uncertainties involved. Philosophical and ideological turf battles won't get it done.
West Chester, Pennsylvania
I take issue with the statement that "by now, few scientists of any political persuasion question the reality of human-induced global warming." Many question it. In the same issue, William Gray replies to the statements that greenhouse gases are going up and the globe is warming with "just because there are two associations, changing with the same sign, doesn't mean that one is causing the other." The interview with Gray also makes it apparent that bad things may happen (no funding) to those who are not politically correct. Global warming has been shown to be occurring for tens of thousands of years. It was occurring well before human technology existed and is still continuing today. Many scientists feel strongly that human intervention in this warming process is negligible when compared with the normal forces of nature.
Professor of chemistry, retired
Raleigh, North Carolina
It is curious that an otherwise insightful article on global warming contains no mention of population. At the Population Summit of the World's Scientific Academies in 1993, 58 national academies of sciences stated, "Humanity is approaching a crisis point with respect to the interlocking issues of population, environment, and development" and reminded people that science alone cannot solve population-based problems, such as global warming. Carbon emissions are linked to demographics, a topic too long pushed under the political-correctness rug.
Rio Rancho, New Mexico
Like William Gray, I am not so sure I am 100 percent convinced of human-induced global warming, but he thinks it is "grossly exaggerated," trashing the works and theories of so many other scientists. Regardless of whether fossil fuels cause global warming, it's a fact that we have soot, toxins, particulates, heavy metals, and a host of other problems (water and soil pollution) arising from the overuse and abuse of fossil fuels. Are dark brown clouds over cities filled with asthmatic children grossly exaggerated?
Studio City, California
IN DAWKINS'S DEFENSE
Shame on Discover for the flogging of evolutionist Richard Dawkins ["Darwin's Rottweiler," September] and its blatant use of the double standard. Those who would undermine the separation of church and state are growing bolder with time, fundamentalists are murdering in the name of their faith, yet woe betide anyone daring to criticize the illogic and intolerance of the religious fanatic. I have met Dawkins on several occasions and found an exceptionally gracious, deeply thoughtful, and sincere individual. If his defense of evolution and science is fierce, it is because the debate, no longer merely academic, warrants it. In battling the insidious incursions of the religious into our secular life, indignation is justifiable. We are fortunate to have such a courageous soul among us.
Cassini Imaging Team Leader
CICLOPS/Space Science Institute
In an illustration for "Exploring Earth's Inner Core/Moon" [Frontiers of Science, October], we stated that Earth's center rotates "once every 23.89 hours—or 0.2 percent faster than Earth." The core actually rotates once every 23.93 hours and moves 0.2 degrees ahead of the outer Earth every year. In "Futuristic Fruits of the Loom" [Reviews, September], we stated that the landing of the Pathfinder probe on Mars in 1997 was "humankind's first imprint on the soil of a planet other than its own." The twin Viking crafts landed on Mars in 1976. In "How Loyal Was Lucy?" [R&D, September], we wrote that previous studies on Australopithecus afarensis were flawed "because they were based mainly on estimates of a single body part, the knee joint or femoral head." A recent study by Philip Reno and his colleagues used the ratios between the diameter of Lucy's femoral head and other parts of her skeleton to estimate the femoral head diameter of other A. afarensis specimens.